Residual current monitors (RCM) with an external transformer are suitable for detecting residual currents. The residual current sensitivity and response time can be set using mini-DIP switches. The residual current relays RD2, in conjunction with an external toroidal core transformer TR..., allow earth fault protection of cables and devices. They are designed for use in single- and three-phase networks with higher rated currents. The modular transformer TRM (transformer diameter 29 mm) is designed to be snapped onto the DIN rail, the remaining transformers TR (transformer diameter up to 110 mm) are designed to be screwed on. If an earth fault current (pulse current sensitive) occurs, the transformer transmits a signal to the residual current relay, which evaluates it and compares it with the set value. If the set value is exceeded, the output relay is switched after the set time and the red LED lights up. The sensitivity (residual currents) and response time of the relay can be set using mini-DIP switches. A changeover contact is available as an output. The connection between the relay and the converter is always checked. If this is interrupted, the relay switches after the set response time. The test button simulates a differential current. When this is pressed, the relay switches without delay, regardless of the response time set. The RD2 changes to the alarm status. The reset button sets the relay to its initial state.
